The United States this week imposed sanctions on two people on opposing sides of the ethnic violence in South Sudan

By Drazen Jorgic

JUBA, May 9 (Reuters) - The European Union, among South Sudan's biggest aid donors, is considering sanctions against people who commit human rights abuses or block talks to end nearly five months of fighting there, the EU ambassador to Juba said on Friday.

The United States on Tuesday imposed sanctions on two people on opposing sides of the ethnic violence in South Sudan, venting increasing U.S. frustration with leaders in Africa's youngest country that it helped create.

Washington penalised Peter Gadet, an army commander loyal to rebel leader Riek Machar, and Major-General Marial Chanuong, the head of President Salva Kiir's presidential guard. The decision freezes any of their assets in the United States and blocks U.S. people or companies from dealing with them.

Ambassador Sven Kuehn von Burgsdorff told Reuters in the capital Juba that the EU may follow up with similar sanctions.

"The EU is actively considering the possibility of targeted restrictive measures, so-called sanctions, against individuals obstructing the peace process and committing egregious human rights violations or war crimes," he said.

Asked to elaborate, a European Union diplomat at the bloc's headquarters in Brussels said: "EU officials are due to discuss possible sanctions against South Sudan at working level next week, but no decisions have been taken so far."

Kiir and Machar are due to meet in Addis Ababa on Friday for the first time since clashes between rival army factions erupted in the capital on Dec. 15 and spread across a grindingly impoverished country roughly the size of France.

The conflict has increasingly taken on ethnic dimensions, pitting Kiir's Dinka people against Machar's Nuers, while crippling the South Sudanese economy and slashing economically vital oil output by a third.

The United Nations accused both government and rebel forces on Thursday of committing crimes against humanity, including murder, rape and other sexual violence, during months of fighting that has killed thousands of people.

Hilde Johnson, head of the U.N. mission in South Sudan, told Reuters the violence had "put the country back decades" and that the damage could be irreversible if it did not stop soon.

A ceasefire agreed in January has been violated by both sides. The regional bloc IGAD, Western powers and China are prodding both sides to abide by the signed truce or come up with a new agreement to cease fighting.

"Once we have a proper cessation of hostilities agreement, I would expect it that also breaching the ceasefire agreement would be a reason to consider applying and deploying sanctions," Burgsdorff said.

More than a million people have been displaced by the bloodshed and the United Nations fears it could spiral into outright genocide and cause famine if left unchecked.

"The international community cannot sit idle with folded arms and look at terrible atrocities," said Burgsdorff. "We need to intervene." (Additional reporting by Justyna Pawlak in Brussels, editing by George Obulutsa and Mark Heinrich)